He and the other two top gear guys say that about literally every car they test

Actually pretty far from the truth. They do give many many accolades for well-made cars, but I have never heard such a blanket "Best car ever" statement from them before. Make of it what you will but I think theres some merit to their opinion ;]

They do throw the word "best" around way too much. BUT, they will always come back to the same answer if you keep asking them over the years, and I think that is F40. (at least for Jeremy and Captain Slow.

He and the other two top gear guys say that about literally every car they test

Actually, over time it's clear the guys have certain favorites. Hammond actually does like BMWs and was one of the first people to get a Z4 roadster. Clarkson's owned several Mercedes-Benzes, new and old, and particularly likes AMGs. May, unsurprisingly, seems to like cars that are quirky, different, or use a new technology, and has a weakness for Italian cars.

It's advertising guys, it's all that it is...advertising, not saying that BMW aren't great cars, but the probably is some other great cars out there and even better ones...maybe not for the regular driver.

They do throw the word "best" around way too much. BUT, they will always come back to the same answer if you keep asking them over the years, and I think that is F40. (at least for Jeremy and Captain Slow.

The F40 is an icon.No doubt. But JC being chauvinistic would choose the McLaren F1 I guess?